cp's OEIS Frontend

This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

A207019 Number of n X n 0..1 arrays avoiding 0 0 0 and 0 1 1 horizontally and 0 0 1 and 1 0 1 vertically.

Table of values

n a(n)
1 2
2 16
3 90
4 558
5 3315
6 16038
7 95900
8 492932
9 2542374
10 14009768
11 70576726
12 371721351
13 1947251540
14 9924535935
15 51877222492
16 266862076008
17 1370454630930
18 7087023247175
19 36312119188998
20 186625648529320
21 958786992765737

List of values

[2, 16, 90, 558, 3315, 16038, 95900, 492932, 2542374, 14009768, 70576726, 371721351, 1947251540, 9924535935, 51877222492, 266862076008, 1370454630930, 7087023247175, 36312119188998, 186625648529320, 958786992765737]

Started in 1964 by Neil J. A. Sloane | Maintained by The OEIS Foundation Inc.

Content is available under The OEIS End-User License Agreement.